docs: def et2utc(et, formatStr, prec, lenout=_default_len_out):
      """
      Convert an input time from ephemeris seconds past J2000
      to Calendar, Day-of-Year, or Julian Date format, UTC.
  
      http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/et2utc_c.html
  
      :param et: Input epoch, given in ephemeris seconds past J2000.
      :type et: float
      :param formatStr: Format of output epoch.
      :type formatStr: str
      :param prec: Digits of precision in fractional seconds or days.
      :type prec: int
      :param lenout: The length of the output string plus 1.
      :type lenout: int
      :return: Output time string in UTC
      :rtype: str
      """
      et = ctypes.c_double(et)
      prec = ctypes.c_int(prec)
      lenout = ctypes.c_int(lenout)
      formatStr = stypes.stringToCharP(formatStr)
      utcstr = stypes.stringToCharP(lenout)
      libspice.et2utc_c(et, formatStr, prec, lenout, utcstr)
      return stypes.toPythonString(utcstr)